Role of regulatory small peptides in the control of gene expression. Francois Payre^1,2, Emilie Benrabah^1,2, Jennifer Zanet^1,2, Serge Plaza^1,2. 1) Center for Developmental Biology, University of Toulouse,Toulouse, France; 2) CNRS, UMR5547, Toulouse France.

   Recent high throughput studies have established that animal genomes express thousands of long non-coding RNAs (lncRNAs). However, small ORFs (i.e., <100 codons, called smORFs) are pervasive among lncRNAs and there is growing evidence that at least some smORFs are actually translated in small peptides. While the abundance of smORF-encoded peptides is likely underestimated, their functions and mechanistic roles are largely unknown. To address this question, we are focusing on the functional characterization of a long RNA that exerts its activity through the production of four small peptides. Previous works indicated that these smORF peptides are required at distinct steps of Drosophila development to control specific transcriptional programs. We report on new findings providing insights into the underlying molecular mechanisms.